is (uncountable) the state of being subadditive.

(of a function) such that the image of a sum is at most the sum of the images of the summands.

## English

### Noun

• (uncountable) The state of being subadditive.
• The statement that a function is subadditive.
• #### Antonyms

• The square-root function is subadditive under addition because $\sqrt\left\{a+b\right\}\le\sqrt a+\sqrt b$.